Write and solve the equation and then check your answer. Select the correct statements for each blank.

A number decreased by sixty-eight is thirty-one.



(5 points)
Equation: ____

This is a _____ problem.

To solve the equation, _____ ___ to both sides of the equation.

To check the solution, ______ 99 for the variable in the equation.

1 answer

Let's break down the problem step by step.

  1. Equation: We need to write an equation based on the statement: "A number decreased by sixty-eight is thirty-one." If we let the variable \( x \) represent the unknown number, the equation would be: \[ x - 68 = 31 \]

  2. This is a: The problem is a subtraction problem, since it involves decreasing a number (subtracting).

  3. To solve the equation, we need to add 68 to both sides of the equation. The adjustment will isolate \( x \): \[ x - 68 + 68 = 31 + 68 \] \[ x = 99 \]

  4. To check the solution, we need to substitute 99 for the variable in the equation. We can verify by plugging the value back into the original equation: \[ 99 - 68 = 31 \] Simplifying it gives: \[ 31 = 31 \] This confirms that our solution is correct.

Now let's fill in the blanks:

  • Equation: x - 68 = 31
  • This is a subtraction problem.
  • To solve the equation, add 68 to both sides of the equation.
  • To check the solution, substitute 99 for the variable in the equation.